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Partial exact controllability and exponential stability in higher-dimensional linear thermoelasticity

Weijiu Liu (2010)

ESAIM: Control, Optimisation and Calculus of Variations

The problem of partial exact boundary controllability and exponential stability for the higher-dimensional linear system of thermoelasticity is considered. By introducing a velocity feedback on part of the boundary of the thermoelastic body, which is clamped along the rest of its boundary, to increase the loss of energy, we prove that the energy in the system of thermoelasticity decays to zero exponentially. We also give a positive answer to a related open question raised by Alabau and Komornik...

Partial exact controllability of a nonlinear system.

A. K. Nandakumaran, R. K. George (1995)

Revista Matemática de la Universidad Complutense de Madrid

In this article, we prove the partial exact controllability of a nonlinear system. We use semigroup formulation together with fixed point approach to study the nonlinear system.

Partially observed optimal controls of forward-backward doubly stochastic systems

Yufeng Shi, Qingfeng Zhu (2013)

ESAIM: Control, Optimisation and Calculus of Variations

The partially observed optimal control problem is considered for forward-backward doubly stochastic systems with controls entering into the diffusion and the observation. The maximum principle is proven for the partially observable optimal control problems. A probabilistic approach is used, and the adjoint processes are characterized as solutions of related forward-backward doubly stochastic differential equations in finite-dimensional spaces. Then, our theoretical result is applied to study a partially-observed...

Particle filter with adaptive sample size

Ondřej Straka, Miroslav Šimandl (2011)

Kybernetika

The paper deals with the particle filter in state estimation of a discrete-time nonlinear non-Gaussian system. The goal of the paper is to design a sample size adaptation technique to guarantee a quality of a filtering estimate produced by the particle filter which is an approximation of the true filtering estimate. The quality is given by a difference between the approximate filtering estimate and the true filtering estimate. The estimate may be a point estimate or a probability density function...

Passivity based stabilization of non-minimum phase nonlinear systems

Juan C. Travieso-Torres, Manuel A. Duarte-Mermoud, Petr Zagalak (2009)

Kybernetika

A cascade scheme for passivity-based stabilization of a wide class of nonlinear systems is proposed in this paper. Starting from the definitions and basic concepts of passivity-based stabilization via feedback (which are applicable to minimum phase nonlinear systems expressed in their normal forms) a cascade stabilization scheme is proposed for minimum and non-minimum phase nonlinear systems where the constraint of stable zero dynamics imposed by previous stabilization approaches is abandoned. Simulation...

Past, Present and Future of Brain Stimulation

J. Modolo, R. Edwards, J. Campagnaud, B. Bhattacharya, A. Beuter (2010)

Mathematical Modelling of Natural Phenomena

Recent technological advances including brain imaging (higher resolution in space and time), miniaturization of integrated circuits (nanotechnologies), and acceleration of computation speed (Moore’s Law), combined with interpenetration between neuroscience, mathematics, and physics have led to the development of more biologically plausible computational models and novel therapeutic strategies. Today, mathematical models of irreversible medical conditions...

Patchy Vector Fields and Asymptotic Stabilization

Fabio Ancona, Alberto Bressan (2010)

ESAIM: Control, Optimisation and Calculus of Variations

This paper is concerned with the structure of asymptotically stabilizing feedbacks for a nonlinear control system on n . We first introduce a family of discontinuous, piecewise smooth vector fields and derive a number of properties enjoyed by solutions of the corresponding O.D.E's. We then define a class of “patchy feedbacks” which are obtained by patching together a locally finite family of smooth controls. Our main result shows that, if a system is asymptotically controllable at the origin,...

Patterns and Waves Generated by a Subcritical Instability in Systems with a Conservation Law under the Action of a Global Feedback Control

Y. Kanevsky, A.A. Nepomnyashchy (2010)

Mathematical Modelling of Natural Phenomena

A global feedback control of a system that exhibits a subcritical monotonic instability at a non-zero wavenumber (short-wave, or Turing instability) in the presence of a zero mode is investigated using a Ginzburg-Landau equation coupled to an equation for the zero mode. The method based on a variational principle is applied for the derivation of a low-dimensional evolution model. In the framework of this model the investigation of the system’s dynamics...

Peak solutions for an elliptic system of FitzHugh-Nagumo type

Edward Norman Dancer, Shusen Yan (2003)

Annali della Scuola Normale Superiore di Pisa - Classe di Scienze

The aim of this paper is to study the existence of various types of peak solutions for an elliptic system of FitzHugh-Nagumo type. We prove that the system has a single peak solution, which concentrates near the boundary of the domain. Under some extra assumptions, we also construct multi-peak solutions with all the peaks near the boundary, and a single peak solution with its peak near an interior point of the domain.

Perfect observers for fractional discrete-time linear systems

Ewa Pawluszewicz (2016)

Kybernetika

A perfect (exact) fractional observer of discrete-time singular linear control system of fractional order is studied. Conditions for its existence are given. The obtained results are applied to the detectability problem of the class of systems under consideration.

Performance analysis of least squares algorithm for multivariable stochastic systems

Ziming Wang, Yiming Xing, Xinghua Zhu (2023)

Kybernetika

In this paper, we consider the parameter estimation problem for the multivariable system. A recursive least squares algorithm is studied by minimizing the accumulative prediction error. By employing the stochastic Lyapunov function and the martingale estimate methods, we provide the weakest possible data conditions for convergence analysis. The upper bound of accumulative regret is also provided. Various simulation examples are given, and the results demonstrate that the convergence rate of the...

Performance evaluation based fault tolerant control with actuator saturation avoidance

Boumedyen Boussaid, Christophe Aubrun, Mohamed Naceur Abdelkrim, Mohamed Koni Ben Gayed (2011)

International Journal of Applied Mathematics and Computer Science

In this paper, a new approach regarding a reconfigured system is proposed to improve the performance of an active fault tolerant control system. The system performance is evaluated with an intelligent index of performance. The reconfiguration mechanism is based on a model predictive controller and reference trajectory management techniques. When an actuator fault occurs in the system, a new degraded reference trajectory is generated and the controller calculates new admissible controls. A constraint...

Periodic coordination in hierarchical air defence systems

Piotr Arabas, Krzysztof Malinowski (2001)

International Journal of Applied Mathematics and Computer Science

The subject of this work is the defence planning of a point target against an air attack. The defence system is decomposed into a number of sectors. A direct method of coordination is used at the upper level, while the sectors use a discrete-time event-based model and the description of uncertainty by multiple scenarios of an attack. The resulting problems are solved using linear programming. A comparison of two coordination strategies for realistic attack scenarios and an analysis of effectiveness...

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